<template>
  <div class="article-page" style="overflow-y: auto;">
    <van-nav-bar left-arrow @click-left="$router.back()" fixed>
      <template #title>
        <div class="nav-author" v-show="showNavAuthor">
          <van-image round width="7vw" height="7vw" :src="article.aut_photo" />
          <span class="name">{{ article.aut_name }}</span>
          <span class="line">|</span>
          <span class="follow" @click="follow()"
          :class="{ un: article.is_followed }"
          > {{ article.is_followed ? '关注' : '取消关注' }}
        </span>
        </div>
      </template>
      <template #right>
        <van-icon name="ellipsis" size="5.4vw"></van-icon>
      </template>
    </van-nav-bar>
       <!-- 骨架组件 -->
       <div v-if="loading" class="article-skeleton">
      <van-skeleton title :row="12" />
    </div>
    <!-- 文章主体 -->
    <div class="article-wrapper" @scroll="onScroll" ref="wrapper">
      <!-- 头部：标题 时间 作者 -->
      <div class="header" ref="header">
        <h3 class="title">{{ article.title }}</h3>
        <div class="time">
          <span>{{ article.pubdate }}</span>
          <span>|</span>
          <span>{{ article.read_count }} 阅读</span>
          <span>|</span>
          <span>{{ article.comm_count }} 评论</span>
        </div>
        <div class="author van-hairline--bottom">
          <van-image
            round
            width="10vw"
            height="10vw"
            :src="article.aut_photo"
          />
          <span class="name">{{ article.aut_name }}</span>
          <van-button
            v-if="article.is_followed"
            round
            size="small"
            @click="follow"
          >取消关注</van-button>
          <van-button
            v-else
            round
            size="small"
            color="#FC6627"
            @click="follow"
          >+ 关注</van-button>
        </div>
      </div>
      <!-- 内容：文章内容 -->
      <div class="main" ref="main" v-highlight>
        <div class="html" v-html="article.content"></div>
        <div class="space"></div>
      </div>
      <!-- 评论：评论组件 -->
      <div v-if="article.art_id">
        <article-comment :article="article" @click-comment="srollToComment">
        </article-comment>
      </div>
    </div>
  </div>
</template>

<script>
import { getArticle } from '@/api/article.js'
import { followAuthor } from '@/api/user.js'
import articleComment from './component/article-comment.vue'
export default {
  components: { articleComment },
  name: 'ArticlePage',
  data () {
    return {
      loading: false,
      showNavAuthor: false,
      article: {},
      toComment: false
    }
  },
  created () {
    this.getArticle()
  },
  methods: {
    async getArticle () {
      this.loading = true
      const [err, res] = await getArticle(this.$route.query.id)
      if (err) return this.$toast.fail('获取失败')
      this.article = res.data.data
      this.loading = false
    },
    onScroll () {
      const wrapperTop = this.$refs.wrapper.scrollTop
      const headerHeight = this.$refs.header.offsetHeight
      this.showNavAuthor = wrapperTop > headerHeight
    },
    async follow () {
      console.log(1)
      const followStatus = this.article.is_followed
      const [err] = await followAuthor(this.article.aut_id, followStatus)
      if (err) return this.$toast.fail('修改失败')
      this.$toast.success(!followStatus ? '关注成功' : '取消关注')
      this.article.is_followed = !followStatus
    },
    srollToComment () {
      const headerHeight = this.$refs.header.offsetHeight
      const mainHeight = this.$refs.main.offsetHeight
      this.toComment = !this.toComment
      if (this.toComment) this.$refs.wrapper.scrollTop = headerHeight + mainHeight
      else this.$refs.wrapper.scrollTop = 0
    }
  }
}
</script>

<style scoped lang="less">
  .article-skeleton {
    padding-top: 60px;
  }
 /deep/ .van-nav-bar__title {
    max-width: 270px;
    width: 270px;
  }
  .nav-author {
    display: flex;
    justify-content: flex-start;
    align-items: center;
    > span {
      font-size: 14px;
      padding-left: 5px;
    }
    .line {
      color: #ccc;
      position: relative;
      top: -1px;
    }
    .follow {
      color: @geek-color;
        // 不加&  ->  .follow .un  ->  后代选择器
      // 加上&  ->  .follow.un   ->  交集选择器
     &.un {
       color: #999;
     }
    }
  }
.article-page {
  .article-wrapper {
    height: 100%;
    overflow-y: auto;
    padding: 44px 0 50px;
    // 头部
    .header {
      padding: 0 16px;
      .title {
        font-size: 20px;
        font-weight: normal;
        padding: 10px 0;
        margin: 0;
      }
      .time {
        font-size: 12px;
        color: #999;
        span:nth-child(2n) {
          margin: 0 5px;
          color: #ccc;
          position: relative;
          top: -1px;
        }
      }
      .author {
        display: flex;
        align-items: center;
        padding: 10px 0;
        .name {
          flex: 1;
          padding-left: 10px;
          font-size: 16px;
        }
      }
    }
    // 内容
    .main {
      .space {
        height: 16px;
        background: @geek-gray-color;
      }
      .html {
        word-break: break-all;
        width: 100%;
        overflow: hidden;
        padding: 20px 16px;
        /deep/ img {
          max-width: 100%;
          background: #f9f9f9;
        }
        /deep/ pre {
          white-space: pre-wrap;
          code {
            white-space: pre;
          }
        }
      }
    }
  }
}
</style>
